How does a fertilied egg become a human?

How does a fertilized egg become a human?  That was one of the questions that Wired magazine (2/07) listed as unanswerable.  Here's what Steve Olson author of Mapping Human History had to say:

     Imagine that you place a 1-inch-wide black cube in an empty field.  Suddenly the cube makes copies of itself--two, four, eight, 16.  The proliferating cubes begin to form structures--enclosures, arches, walls, tubes.  Some of the tubes turn into wires, PVC pipes, structural steel, wooden studs.  Sheets of cubes become wallboard and wood paneling, carpet and plate-glass windows.  The wires begin connecting themselves into a network of immense complexity.  Eventually, a 100-story skyscraper stands in the field.

     That's basically the process a fertilized cell undergoes beginning with the moment of conception.  How did that cube know know to make a skyscraper?  How does a cell know how to make a human (or any other mammal)?  Biologists used to think that the cellular proteins somehow carried the instructions.  But now proteins look more like pieces of brick and stone--useless without a building plan and a mason.  The instructions for how to build an organism must be written in a cell's DNA, but no one has figured out exactly how to read them.

     This is the mystery of life.  God is the grand architect and mason who draw the plans and oversees the construction.  David recognized this 3,000 years ago,

     For you created my inmost being; you knit me together in my mother's womb. 
     I praise you because I am fearfully and wonderfully made; your works are wonderful, I know that full well.
     My frame was not hidden from you when I was made in the secret places.  When I was woven together in the depths of the earth, you eyes saw my unformed body.  (Psalm 139:13-15, NIV)

     It is my prayer that someday those who hold to a pro-abortion stance will admit that abortion destroys a human life that is fearfully, wonderfully, mysteriously made by God.  Calling an unborn child a fetus is simply a way of rationalizing an unthinkable destruction of human life.  Unless all human life is valuable, no human life is valuable.